First Trimester U/S Preparation

The following information is a general guide to preparing for a first trimester and early dating ultrasound at BWU. If the preparation required for your appointment varies from the below, our reception staff will inform you and advise new instructions at the time of booking.

Transabdominal U/S

A transabdominal ultrasound is a non-invasive imaging test used to examine the growing baby and the maternal structures (uterus, ovaries, placenta), from outside the body. During the procedure, a clear gel is applied to your lower abdomen, and a handheld device, called a transducer, is moved across the skin. The transducer sends out sound waves that create images of the internal organs on a screen.

Transvaginal U/S

A transvaginal ultrasound is considered the gold standard for imaging in the first trimester (<14wks) and the maternal pelvic organs, particularly the cervix and its relationship to the developing placenta. Unlike an abdominal ultrasound, this procedure involves inserting a small, wand-like probe (called a transducer) into the vagina. The probe uses sound waves to create detailed images of the inside of your pelvis. It might feel a little uncomfortable, but it shouldn’t be painful.

As the patient, it is your right to consent or decline an internal ultrasound at any stage. Please speak to one of our friendly team for more information or to discuss any concerns you may have.

If you require further instruction or have any questions regarding the above, please discuss with our admin team.

Dating & Viability U/S | Pre NIPT U/S

Unless expressly declined, all pregnancy scans with a gestational age <11wks will require an internal (transvaginal T/V) ultrasound. T/V ultrasounds provide the most detailed images of the growing embryo to ensure the most accurate measurement of their size, heartrate and general development. 

T/V ultrasound allows a more detailed assessment of the uterus (baby’s home) for the location of the pregnancy and any sign of bleeding, as well as, a general assessment of the ovaries and pelvis to ensure there is no ectopic pregnancy or other concerning features to note.

Please see more information below in preparing for a transvaginal ultrasound.

1st Trimester/Early Anatomy U/S

This scan is usually done between 12 and 14 weeks of pregnancy to assess the risk of chromosomal conditions and the early anatomy of the baby. To get the best images, a combination of transabdominal (T/A) and transvaginal approach may be required. As such, we recommend you arrive with a comfortable bladder, you do not need to be full, but it is advised that you do not use the bathroom in the 30-minutes prior to your scan. Please wear comfortable, loose clothing for easy access to your lower abdomen. No fasting is required, and there are no special dietary restrictions prior to the scan. 

Be sure to bring any relevant medical records including NIPT results (if not done through BWU). 

This scan requires very specific imagery for diagnostic accuracy, depending on the position of the baby this scan may take anywhere from 20-minutes to 1-hour.